stoner



Re, `16,4s4

Nov. 23 1926.

G. H. STONER BRAKE Original Filed Jan. 5, 1925 2 Sheets-Sheet IIII/enar Gewehr mfg'.

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Nov. 23,1926. Y Re. 16,484

G. H. STONER BRAKE Original Filed Jan. 5, 1925 2 Sheets-Sheet 2 Inventar gggyeilolwr 1 5 Z" ma? Reissued Nov. 23, 1926,

UNITED STATES Re; 116,484l

PATENT OFFICE.-

GEOBGE H. STONER, OF EAST BOSTON, MASSACHUSETTS, ASSIGNOB T0 TRU-ARC INC.,

OF BROOKLINE, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

, vBRAKE Original No.1,550,399, dated August 1B,

My invention as herein involved relates to brakes and particularly to those of expanding type such as are installed inautomobiles and like vehicles.

Much difficulty has been experienced with such brakes in regardto inequalities of wear and difficulties of adjustment with the result that it has been difficult, if not impossible, to maintain the efficiency ot such brakes for any considerable period of use. I

- In such brakes much difiiculty has been experienced in devisingexpansion members which would under given conditions apply uniform or nearly uniform radial resistance to the brakev drum. To supply such a brake andsuch an internal expansion ratus has been the urge of my thought. I have provided for general principles and at the same time have devised specific apparatus of immediate and practical utility in solving some of the brake problems of standard automobile construction as appears in automobile use.

In accordance with my able to provide a simple and effective brake having a great uniformity of bearing surface and having a wide range of adjustment which can be very easily made to take up such wear as is inevitable.

My invention is therefore to not only as a brake but as a nism capable of installation be considered braking mechaor substitution in existing cars and particularly in certain cars t0 which its immediate applicability will be obvious to those skilled in the art.

As illustrative of my inventlon I have shown in the accompanying drawings a form of brake which I have found to be very eflicient and one which can be readily embodied in a new car or substituted in an old car without any increase in expense and with a considerable ultimate saving. Throughout the specification and drawings like reference vcharacters are employed to indicate corresponding parts, and in the drawings zi Fig. 1 is a side elevation'partly in section of a brake in accordance with my invention.

Fig. 2 is a central vertical section.

Fig. 3 is a fragmentary view like Fig. 1 but with the member expanded,and

Figs. 4, 5, 6 and 7 are diagrammatic views 1925, serial no. 304, filed January 3, 1925. reissue led April 22, 1926. Serial No. 103,975.

appa-v inventi'on I am Application for illustrating individual and relative adjusta-v bility of the segments.

I have lindicated at of an automobile wheel, and at 2 a portion of the usual external contracting .band oper-V ating thereon. vithin such a drum I provide as an expansion member a construction which is in part rigid land in part flexible, as will be hereinafter described.

Primarily, my expansion member consists ot flexible or resilient bands or strips 3, 3

vwhich are united by a hinge member 4 to which they are adjustably connected by threaded studs 5 reversely threaded at their opposite ends into the blocks 31 and one ot the hinge members 4 which slip on the bracket pintle I. On each one of the bands 3 I rivet a pair of members 7 and 8. The

1 the usual brake drum' member 8 is tapped to receive a reversely threaded adjusting screw 9 the other1 end of whichis tapped into the member 7 so as to provide for the adjustment ot' these members. The reverse threading of the members 9 is indicated at 11 and lock lnuts 111 are provided for holding their adjustment in the blocks 7 and 8. The two members 7 are yieldingly held together in contracted position by a spring 10.

IVhen properly adjusted my brake gives great uniformity' of contact and consequently uniformity of wear. While in many cars the brake shoes are readily accessible or adjustment, my brake shoes may be initially adjusted by mounting them in a test drum ot' the'size to which they are to be applied. For example, in the service station, I have standard drums for; the make of car to be equipped. .In such test drums, I

fix a dummy anchor pin which occupies the 12 or a block of like thickness simply to gauge this circumferential movement and give the ends of the segments contact with brake equipment of the.

the cam 12 of the car whenthe segments are mounted in place after adjustment.

All this adjustment, above referred to, is preliminary to installation. After installing, the brakes are on their usual permanent anchor pinand can be adjusted against their permament cams. j

To compensate for the inevitable'wear of the cam 12 on the readjustment after recurving the segments, the studs 5 may be adjusted so that no shimming or welding of additional bearing surface is required. The studs 5 simply peripherally relocate the segments 3 until their end 15 blocks -7 are in proper relation to the cam 12. When the cam 121s actuated it forces apart the blocks 7, the resultant force through the connection 9 moving the entire se ent outward as a unit. This movement 1s substantially radial and the bands, 3respond to it to ei'ect a substantially uniform brakin action.

The foregoing a justment'may be es t understood in its geometrical' characteristlc by reference to the diagrammatic Figs. 4 to 6. In these figures I have indicated by the circle 21 the outline of the brake drum. yInscribed in this circle 21 are two arcs 31 which in Fig. 4 are drawn intentionally in nonconforming relation to the circle 21"to indimembers of the brake when not in properly adjusted position. Connecting the ends of f these arcs I have drawn li-nes 91 which con- Atute chords for the arcs and indicate'the "af-lines of chord adjustment in flexing or changing the curvature of the arcs 31.

l In Fig.- 5 the arcs 31 are by the chords 91 to substantial .wirtliflthe indicated' drum 21.

con ormity In practice the eiadj usted to a very close parallelism.

g1-6 I have shown the arcs 31 so adjuste'd'f-by expansion as indicated by the arrows to bring their open ends adjacent to the cam 12 indicated in dotted lines in the diagram. This corresponds generally to the osition of the parts shownin Fig. 1 of the rawin s.`

In Fig. 7 I have shown theselgments 31 and 91 ex anded by the cam 12.

olution o the force so exerted these segments are moved substantially radially outward as indicated by the arrows so as to kgive a maximum of unlformity 'in the contact of the arc surfaces with the enclosin circle 21. The diagram in Fig. 7 is intendzed to correspond l -enerally with the position of the parts ghown in F' 3. c My expansion members may be substitutedI Icertam standard brakes replacing more @c hersome rigid parts. All that is necessary'to do is to remove these specific 'rigid expansion members and substitute my str1 s ,3, slipping the hinge member 4 over t e usual pintle P, and adjusting the threaded Studs 5 to properly position t e end bearings blocks 7 as well as to make' l jacent an end of cate a theoretical position of the expansionl shown ex; anded y the resof the castings 7 against the operating cam. his replacement can be made in less time and with less expense than is'required in relining Aand readjusting certain standard brakes which do not have uniform bearing nor an internal adjustment. i

Various modifications may obviously be made in the design of the blocksv and the character of the adjustments,` all without departing from the spirit of my invention if within the limits of the appended claims.-

That I therefore claim and desire to secure by Letters Patent is:

1. In a brake of the class described, an expansion member comprising a pair of flexible band segments pivotally mounted adeach, a bearing adjacent the opposite end of, each of said se ents, means for adjusting each segment with reference to a subtendedchord, and means for relatively moving the segments circumferentially with reference to an enclosingfbrake drum. 2. In a brake, an expansion member comprising a ilexibleb'and segment, and a rigid adjustlng piece effectively disposed with reference thereto in the line of a subtending chord, a hin e member for supporting said segment, an means for positively adjusting said se ment relatively to said hinge. In a rake of the class described, an expansion member comprising a flexible c and, a pair of rigid members permanently connected ad'acent the ends thereof, an adjstable rigi strut between said rigid memrs, a hinge member and an adjustable connection between said expansion member andl said hinge member.

'4. In a brake of the class described, an expansion member therein comprising a pair 1.05 of flexible band segments, means for adjustably bending sd flexible segments, a hinge member connectin the segments, .and adhe hinge member for circumferentially adjusting them with refer- 110 ence to an enclosing brake drum.

5. An expansion member for a brake, comprising a pair of fiexible arc shaped bands, means foradjustin the curvature of said bands, and means' or adjusting the bands 115 circumferentially with relation to a substantially concentric enclosing circle.

f 6. In a brake mechanism, a pair of expansion members each comprising a flexible arc shaped band, means for adjustin the curva- 12" ture of said bands, means for a justing the bands circumferentially with relation to a substantially concentric enclosin brake drum, and means for expanding t e band se ent to engage the drum. j

In a brake ofthe class described, an exansion member comprising a pair of flex- 1 le band se ments hinged in relative circumferential afjustment'at one end of each, a block permanently connected adjacent each 1.3.0

end of each of said segments and adjustable rigid struts between the block segments, the

block at the free end'of each segment having an operating bearing each disposedin oppo- 5 sition to the other.

8. In a brake of the claas described, 'an expan,s ion member comprlsinga pair ofl flexv ible band segments, a hinge member at one end of each, a block permanently connected 19v adjacent each end of each` of said segments, and an adjustable rigid strut between 'the blocks of each segment,V and an adjust-ing piece rcarried attherst mentioned end of v each segment and connected in `adjusting re- 'flation to its hinge member.

9. In a brake, a brake drum having an internal friction shoe including an arc member,

means for positively adjusting theeeifective radiusl of said aro member, an expanding devlce vfor said shoe, and means for relative adv circumferential zo-operative adjustment between the shoe and the expansion device.

In testimony whereof ax my signature.

GEORGE H. STVONER. 

